Vehicle suspension



Dec.' 14 1926. l

` A. DAVIDSON 1 VEHICLEKSUSPENSION- 2 Sheets-Sheet 1 Filed April 9. 192; v

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Dec. 14, me. f, 1,610,754

A. DAViIDSON VEHICLE SUSPENSION Filed April 9, 1921 2 sheets-sheet 2 lilill "lll I'III l ,11 um A l 4 fm Patentedl Dec. 14, 1926.

UNITED STATES .ARCHER DAVIDSON, OF BROOKLINE, MASSACHUSETTS.

VEHICLE SUSPENSION.

Application led April 9,

Among the principal vobjects which the vpresent invention has in view are: To rovide an improved suspension of greater exibility than has heretofore usually been ema ployed in a vehicle; to vary the elasticity of the suspension of a vehicle in correspondence with service conditions; to' approximately maintain the normal relation of the body and running gear of the vehicle by varying the elasticity of the suspension; to provide auxiliary retarding means to slow the movement or modify the elasticity of the suspen-V sion, absorb shocks, and adapt the suspension to service conditions; to vary the retardingl means of the suspension in correspondence with the speed of travel of the vehiclegfto provide power and manually operated means at will to vary the flexibility ofthe suspension; to provide co-operative'V power and d5 carrying the above stated objects intoeiect.

Drawings Figure l is a plan view of a rear portion vof a vehicle chassis and running gear there-v for, and a suspension mechanism operatively connecting the same, constructed and arfranged in accordance with the present in- Y vention;

Figure 2 is a vertical side viewof the same;

Figure 3 is a detail view showing a fragment .of the side bars of the chassis, riding spring, bar thereof, and an axiliary spring for varying the spring carrying power of A Figure t is a detail view on enlarged scale in verticalfsection of a dash pot and controls therefomi operatively connected with the carrying springs to retarder .l modify i the flexibilityljthereof, the section -being taken aston the lined-5t in Figure 1; Figure is a side view of a-'pmodiiedform` of suspension, constructed andarranged-.inlaccor'lancelwith the present inv'entif'm;A

Figure lis a rearview thereofg.- f f, Figure i7 s a cross section. ,of-lav m dified' spring .connecting memberfa'nd an .axi'liaryf-` supporting bar thereforpthe section being takenfas on' the line 'if-7 in Figure 1.l f f 5i Heretoiore, vehicle suspensions: wherein manually operated meansto vary the retardl 1921. Serial No. 459,961.

carryingl 'springs of maximum exibilit have been employed toprovide an easy ri springs employed, they have been of a flexibility to provide maximum riding comfort with the vehicle fully loaded resulting in the suspension being not sufliciently flexible to give maximum riding com-fort for ,what is termed light load conditions. An ideal condition that has been sought has been to provide a suspension so that it can be ar ranged for maximum possible flexibility with various loads carried by the vehicle, that-will support various loads without excessive displacement of the 1 vehicle body, and will provide maximum flexibility without permitting objectionable service swing or side sway of the vehicle body. In the.

present invention elastic auxiliarydevices are-employed' to vary the flexibility of the suspension in correspondence with the' service load of the vehicle and which co-opera- 'tively approximately maintain'the normal relation of the body and runninggear' of the. vehicle, and torsion devices operatively connecting together the various elastic meansl of the suspension are employed to prevent disagreeable service swing or side sway'of the vehicle body. f

It has also been ascertained that a vehicle travelling at a high rate of speed requires a y 'suspension of different elasticity than oneslow speeds it 'has not been suitable for high' speeds. Various types of shock absorbers or retarding mechanisms have' been employed to overcome these difficulties by retarding or imodifying theelasticity of the suspension,

but they have not heretofore been readily adjustablewith the vehicle in motion, nor have they been arranged to automatically rovide 4 great-er oir-.less retarding eiect on't e suspension in correspondence with the speed of the vehicle. Furthermore, the employment of some typesofthose means has 'resulted in al disagreeableswingor side-sway of the vehicle body.. vIn the present invention aux-` illary retarding mechanisms are employed which are varied with the vehicle in motion to retard or modify the elasticity of the suslnain carr in@ s rinO's r12 of the cantilever r P3 D type, being connected to the vehicle axle 13 in an improved manner, and to the body of the chassis 14 by swinging shackles15 and saddle 16 and clip plate 17 to which it is bolted. The'body of the spring 12 is carried between the plate 17 and the saddle 16. The ysaddle 16 at each side of the vehicle is rigidly connec-ted to a cross or jack shaft- 18, 'which is suit-ably mounted by ball or other friction reducing bearings in the housings 19 in the side bars of the chassis 14. By connecting the saddle 16 and the spring 12 held thereby to the shaft 18 which is held in place by the bearings 19 on the chassis of the vehicle, excessive swingor sway of the body is eliminated.

As is usual in springs of the type referred to, the springs rock on their center bearings,

pivotal connections being provided to that end. In the present invention the shaft 18 rocks in correspondence with -the flexure of the said springs. When desirable, a torsional flexibility being permitted in the shaft 18 to-admit of a small amount of independent movement of the two springs 12. When `the shaft 18 is made torsionally flexible it is desirable that it should be stiftened by theauxiliary supporting bar 18a, as best seen in Figure 7 of the drawings.

Rigidly connected with the shaft 18 is a bracket yoke 20. The yoke 20 straddles and holds in line a saddle 21, to which is rigidly bolted the butt end of an`auxiliary cantilever spring 22. As seen best in Figure 3 of the drawings, theflexible end of the spring 22 is operatively connected with the swinging shackle 23 mounted on a nut 24. The nut 24 is suspended on a jack screw 25, which is mounted in bearings on a bracket 2G, and has at the upper end a worm wheel 27, the teeth whereof engage the screw 28 on the armature shaft of an electric motor 29. The saddle 21 freely rotates' on the shaft 18, the purpose being to allow for varying the relation between the spring 22 and the bracketr 20, which is rigid with and extended horizontally from the shaft 18. lVhen the nut 24 is lowered, the flexible end of the spring 22 is depressed, andthe spring 22 is moved out of engagement with the bracket 20. Or, if not moved out of engagement, the pressure thereof upon the said bracket. is lessened. A

If the nut 24 is moved upward, the spring 22 is brought into contact with the bracket 20, and the tension of the. auxiliary spring 22 is' increased as the end thereof is raised by the nut and the pressure of the spring 22 on'the yoke 20 is increased. It is obvious that as the force of the spring 22 is exerted upward on the bracket 20, the resistance to the rocking of the shaft 18 is increased. Ashere arranged, it is seen that the springs 12 are more flexible forwardof the jack Shaft 18 than between the shaft 18 and the axle of the running gear. However flexible `the springs 12 are forward'of the shaft 18, it is seen pa deflection, or any activity, of the 'springs 12 causes a rocking of the shaft 18.

T herefore, if the rocking of the shaft 18 be resisted, and the resistance varied, the activity of the suspension is varied.

By raising the spring 22, the strength of the spring 22 is employed to flexibly resist the rocking of the shaft 18, which is'equivalent to adding the Strength of the spring 22 to the strength of that portion of the springs 12 forward of the shaft 18, thereby increasing the strength of the suspension. It is well known that increasing the strength of a suspension decreases its flexibility, and that decreasing the strength of a suspension inerea ses its flexibility. Therefore, by raising or lowering the spring 22 the'flexibility 0f the suspension is varied to most desirably sustain" the various loads carried thereby, and consequently the maximum riding comfort may be obtained under various service conditions. i

lt is obvious, that if loading a vehicle body causes a ilexure of the carrying springs and a. consequent lowering of the vehicle body, that with the springs flexed and Sustaining the load, that if the flexed springs be elevated the loaded vehicle body will be raised and may be restored to V:its original elevation. V*Hence by varying the spring 22 the normalelevation of the vehicle body and ruiming gear may be maintained approximately constant. Y

The motor 29 may able means. shown in Figure 3 of the drawings may be manually operated to reversethe current delivered by the batteries 31 to the motor 29, and thereby reverse the rotation of the screws 28 and 25 and the direc-tion of travel of the nut 24.

Any suitable indicator, such as the pointer 32, and the calibrated lquadrant 33, may be employed to indicate' the osition of the spring 22, the said pointer 3 being connectbe'operated by any suitin the flexible end of the said spring 22.

By operating the screw 25 manually, the

A double throw switch 3() ed by means of a rod 34 wit-h the 'shackle 23 liquid from one ofsaid chambers to thespring 22 may at will be brought into serv-vA ice or its effect may be varied.' l

To provide'an auxiliary retarding mechanism to slow the movement of the springs of the `suuspension and absorb road shock, the shaft 18 has an arm 35, which, as shown best in Figure 4 of the drawings, is connected by means of a rod 36 with a spool iston 37. The disks of the piston 37 are rigi ly united by a bar 38. The chambers 39 and 40 constitute a dash pot construction and are connected by a channel 41 for the transfer of other. The transfer is augmented by e1nploying the ports 42 and 43 in a central partition of a lateral chamber 44. The ports 42 land 43 are furnished with valves 45and'46 respectively, the said ports connecting with outlets for liquid flowing from the chamber 39 to the chamber 40, and reversely from the chamber 40 to the chamberv 39. It will be seen that normally the end of thek arm 35 is raised and lowered in unison with the rock-l ing of the shaft 18. It is also obvious that thespeed of the rise and fall of the said arm, and consequently the speed of rotation of the said shaft, is de vendent upon the passage of liquid through the ports 42 and 43.

The port 42 is controlled by the valve 45 and this is connected by meansof a pull cord 47 with the arm 48 on the rocking shaft 49. The rocking shaft. 49 is connected by means of a second arm 50,and a rod 51 with a flying ball governor 52. The balls 52 are normally contracted by a spring 53the shaft 54 on which the said balls are mounted being rotatably connected with the carrying wheels of the vehicle, a suitable transmission being` provided therefor.

From the foregoing it will be seen that as the speed of the vehicle increases the balls 52 expand and draw upon the rod 51 to rock the shaft 49 and the arm 48 mounted thereon, pulling the cord 47 to lift the valve 45 in closer relation to the port 42. Asthe opening in the port 42is diminished the resistance to the ow of the liquid from the chamber 39 to the chamber 4() is increased and the action of the arm 35 and shaft 18 is retarded.

The valve 46 which controls the opening 'of the port 43 is seated by a spring 54 the tension whereof is manually varied by av The tension of the spring 54 may free moving cylinder 61 with enlarged ends 62 is employed. The cylinder 61 freely slides up and" down as limitel by the ends 62. This free action of the cylinder 61 per- 80 mits a limited free motion of the piston 37,

and consequently the springs of the suspension, with lthe valves and 46 forcibly seated. To permit a further free motion of the springs of the suspension and to merge the free motion provided by 61y into a stronger resist-ance offered by th'e valves 45 and 46 to theinterlow of fluid between chambers 39 and 40, the passage 63 is provided.

From the foregoing jit will be seen that when thus provided a vehicle may be furnished with very flexible springs, the carryf ing power of which may be assisted or augmented by means of an auxiliary spring, which may be brought into action at will, and also that the 'flexibility of the springs, including the auxiliary spring when employed, may be modified and road shocks ab sorbed by an auxiliary retarding ormodifying 'mechanism which may be varied manu- 100 ally at will orfin correspondence with theV specdof the vehicle.

It will be understood that the auxiliary retarding or modifying mechanism Yand the auxiliary spring, either being used separately 105 or in combination with the other,retard or modify the iexibility of the suspension as a whole by modifying the normal flexibility of those portions of the suspension springs 12 forward of the jack shaft 18, while leav- V110 ing the normal flexibility of those portions of the `suspension springs 12 between the shaft 18 and the axle 13 substantially unchanged. Also, since the springs 12 are operatively connected together by the cross 115 shaft 18, those portions of the springs forward ofthe shaft 18 are `flexed simultaneous'- ly, and conseguenti the flexibility of these forward portions o the springs 12, and also of the auxiliary spring 22 when employed, 120 can have no tendency to permit objectionable swing or side-sway of the body of the'vehicle. On the other hand, the combined resistance of those portions of the suspension forward of the shaft 18, including that of 125 the auxiliary retarding means, tends to resist such side-sway. As a result of these facts it will be understood that the carrying springs may be made much more flexible than those heretofore commonly employed without 13 'l' permittin excessive side-sway orswing, and ythat the exibility of those portions of the springs 12 between the shaft 18 and the axle 13 will largely determine, the extent of thev side-swing of the body. in Figures and 6 of the drawings a modified form of the invention is shown, the

modification consisting in that the pull cord 47 is carried over idler pulleys 58 to a-fric lever-56 and the flying -balls 52 operativelyl connected with the running gear of the ve-V hicle may be employed for effecting r altering the operation of any of the wellknown types of shock absorbers, when used in connection with either cantilever or other types of carrying springs or suspension.

Claims: e y1. In a vehicle, a vehicle suspensionl comprisinga plurality of `metal' load carrying suspension members, and means for varying the number'of saidv members in service; a

power supply carriedby said-vehicle; and ineens operable by said power supply and operatively connected to said means for varyy Aing the number of said members in service.

2. A vehicle suspension comprising a plu i rality of vmetal resilient load carrying suspension members, and means for varying the number of said vmembers in service; and means operatively connected with certain of said members andoperable to dispose the same actively and inactively.

. being connected to said cross shaft, said shaft from an axle thereof, bearings of said frame, a cross shaft carried in said bearings, light 'load cantilever springs operatively connected at one end to said axle and operatively connected at their other ends to said vehicle frame, and said springs between said ends being rocked by said springs; auxiliary resilient load carrying means, normally inactive for light loads; means operable by said shaft to engage said auxiliary means for 'service activity; and means operatively disposing said (auxiliary resilient means in ac, tive relation to said shaft for heavy loadscairied by said vehicle. e l

4f. For spring supporting' a vehicle frame from an axle thereof, bearings of said frame,

a cross shaft carried in said bearings, cantilever springs operatively connected -at one end to said axle and o eratively connected f at their other ends to said veliicleframe, and

said springs between said ends being con-l nected to said cross shaft, said shaft beingrocked byy said springs; yielding non-elastic means connected to said shaft to resist the 1,eie,754

ing rocked by said springs; yielding nonelastic means connected to said shaft to resist the rocking of. said shaft to augment the strength of said springs and to slow the rebound of said springs.

6. For a spring supporting a vehicle frame from an axle thereof, bearings of said frame,

a cross shaft carried in said bearings, canti- .lever springs operatively connected at one 'end to said axle and operatively connected at their other ends to said vehicle frame, and

said springs'between said ends being con-- nected to said cross shaft, said shaft being rocked by said springs, yielding non-elastic. means connected to said shaft to resist the rocking of said shaft to 4augment the strength of said springs, and to slow the rebound of said'springs;y and means to, at will, vary said yieldingv means to vary the activity of said springs.

7. For aspringv supporting a vehicle frame from an axle thereof, bearings bf said frame, a cross shaft carried in said bearings, light load cantilever springs operatively connected at one end to said axle and operatively connected at their other ends to said vehicle frame, and said springs being connected to said cross shaft between the ends of said springs, said'shaft being 3. For spring supporting a vehicle frame rockedby said springs, yielding non-elastic means connected to said shaft to augment the strength of said springs and to slow the Vrebound. of said springs; auxiliary resilient 4end to* said axle and operatively connected at their'other ends to said vehicle frame, and

.said springs between said ends being con- `nected to said vcross shaft, said shaft being rocked'pby said springs; an arm=connected to said shaft to be rocked therewith, the end ,i of saidy arm being operatively `:connected to a piston; a cylinder connected to'said frame,

said piston to move in said" cylinder; and T ,y umeans in said cylinder to yieldingly resist the movementiof said piston to retard rocking lof said cross shaft.

9. For spring supporting a vehicle frame from an axle thereof, bearings of said frame,

a cross shaft carried in said bearings, springs operatively connected to said axle and shaft, said shaft to be flexibly rocked by said springs by the activity-of. said' axle; springs operatively connected to said vehicle frame and said cross shaft to flexibly resist the rocking of said shaft;- and nonelastic yielding means connected lto said shaft and to said'vehicle frame to retard the activity of said cross shaft.

10. For spring supporting a vehicle frame from an axle thereof, bearings of said frame, across shaft carried in said bearings, springs operatively connected to said axle and said shaft, said shaft to be flexibly rocked by said springsby the activity of said axle;-

springs operatively connected to said vehicle frame and said cross shaft to flexibly .resist the rocking of said shaft; non-elastic variable yielding means connected to said shaft and to said frame to retard the activity of said-cross shaft; and means to at will, vai'y said non-elastic variable yielding means.

ll. In a power driven vehicle; springs supporting the vehicle frame from an axle thereof, bearings' of said frame, a cross shaft carried in said bearings, said shaft to be fl'exibly'rocked by said springs by the activity of said, axle; springs operatively connected to said vehicle frameQand said cross shaft to flexibly resist the rocking of said shaft, non-elasticl variable yielding means connected to said shaft and to said frame; means to vary said non-elastic variable yieldi ing means; and means operatively connected to said non-elastic` variable yielding means to vai-y said yielding means approximately in correspondence with the speed of said vehicle.

12. In a vehicle, a vehicle suspension comprising, a plurality of elastic' means and constant yielding means operatively disposed to support the frame of said vehicle from an axle thereof, said elastic means and said constant yielding means being operatively connected together by a rockable cross shaft rockablymountedf-nfbearings of the frame of said vehicle.

13. In a vehicle, a vehicle" suspension comprising, a plurality of elastic means an constant yielding means peratively dir'- posed to support the fram of said vehicle from an axle thereof, said elastic means and said slowing means being operatively connected together by a i'oclzable cross shaft rockably mounted in bearings of the frame of said vehicle; and means to vary the relai. tions between said suspension and said vehicle.

14. In a vehicle, a vehicle suspension comprising, a roekable cross shaft roclrably mounted in bearings of the frame of said vehicle, elastic means operatively connected to said cross shaft and to an axle. of said vehicle, elastic means operatively connected to said. cross shaft and the frame of said said nected to the running ivehicle; and constant yielding means disbody and running gear of said vehicle, onev end of said spring being operatively connected to the body of said vehicle,`the other endof said spring and the' intermediate point of support of said spring being operatively connected to the body of said Ivehicle, said intermediate point of support being rocked by the activity of said spring; means operatively connected to said intermediate point ofsaid spring and to said` frame to check the activity of said spring and absorbv shocks. v

16. In a vehicle, a vehicle suspension comprising, a rockable crossl shaft rockably mounted in the frame of said vehicle, said shaft beingA mounted crosswise to said frame; elastic means operatively connected to said cross shaft and to the' axle of said vehicle, said cross shaft being rocked by said elastic means connected to said cross'shaftjand said l being operatively con# gear of said vehicleLI axle; elastic means operatively., coiiected'to said cross shaft and the frameof'saidvehicle to resist the rocking of said cross shaft; and

variable auxiliary means disposedsltol modify the normal elastic activity of;s a id s1spension L by modifying the normal elast@ elastic means connected to...-`saii; and said ity. of said ross shaft normal elastic activity ofgsaidielastic means connected te said cross shaft"Y of said vehicle. .l

A 17. In a vehicle, a vehicleHT v prising a rockablev crpsssliaft rckably mounted in the'frame jOfSaid'yehiCl, said -shaft `being mo'unted cr'osswise'to said frame;

elastic ineansop ratively connecteditd said cross shaft and t an axle of said vehicle, said cross shaft being rocked by said yelastic vehicle 4frame Whi'lee permitting a Iidsaid axle l A uspension commeans connected tosaidcross shaft and said axle; elastic meansv operatively'connected to said cross shaft andthe frame of said vehicle to resist the rocking of said cross shaft; and auxiliary means operatively' connected to said cross shaft and said vehicle frame to modify the normal elasticl relations between said suspensin and; said-veliicle.

18. Iln a vehiclgalvehicle suspension comprising, a rockable-.. crossshaftv rockably mounted in the frame of said vehicle, said shaft being mounted crosswise to said frame; elastic means operatively connected to said cross shaft and to an axle of said vehicle, said cross shaft being rocked by said elastic meansconnectedto said cross shaft and saidaxle; elastic means operatively connected toi: said cross shaft and the frame of said vehicle to resist the rocking of said cross shaft; and

variable auxiliary .means operatively conmated to 'Seide-S3 'Shaft and a', said vehicle frame to vary the relations between saidsus-` cross shaft and' said axle and adapted [to rock'said cross shaft when lsaid axle is moved' relatively. thereto,f.means connected to said cross shaft and to saidjframe forresisting' the rocking of said cross shaft, and means for varying the resistance offered by said means.

20. A vehicle suspension comprising in i combination, a vehicle frame, a 'cross shaft rotatably mounted in lsaid frame, an axle.' elastic members operatively connecting said cross shaft and said axle and adapted to rock said cross shaft when said axle is moved relatively thereto, means connected to Said.

cross shaftv and to said frame for resisting the rocking of said cross shaft, and means for varying the resistance offered by said means`r said last-mentioned means being adapted to be manually controlled at a point remote therefrom.

21.. In a vehicle including a frame and an axle, a spring suspension for supporting said frame from said axle comprising in combination, bearings 'on said frame,.a cross one end to said axle and at the other end to said frame, said springs being connected to said .cross shaft etween their ends and shaft' rotatably mounted. in said bearings, v)cantilever sprmgs operatively connected at adapted to rock said cross shaftv when Said shaftandsaid frame for resisting the rock- ,.axlejisfmovede-relatively' thereto, auxiliary` i meansfoperatively connectedto 'said cross ing of said 'coss4 shaft, .and means fory ,vary-,i

ing said auxiliary means.

22.'In'a'vehicle including a frame and an axle, a spring suspension for supporting said framel from said axle oomprlsing 1n combination, bearings on said frame, a cross shaft rotatably mounted in'said bearings,

cantilever' springs operatively connected at (me end'to said axle and. at the otherend to 'said frame, said springs being connected to said cross `shaft between their ends and adapted to rock said cross shaft when said axle is' moved relatively thereto, auxiliary means o eratiyely connected to said cross shaft an 'said frame for resisting the rock-y ing of said cross shaft, and means for vary; ing said auxiliary means, said last-mem tioned means being' adapted to be manually controlled at-.a pointremote therefrom.

ARCHER DAVIDSON. 

